In recent years, vacuum ultra violet (VUV) light having a wavelength of 200 nm or less is used in a variety of fields aside from the semiconductor exposure field. For example, a technique of patterning a self-assembled monolayers (SAM) by inducing a chemical reaction directly with light with the use of VUV and a mask, without using a pattern forming process with a photoresist, is being developed. A patterned SAM is used, for example, as a gate insulating film for an organic thin film transistor.
In addition, as a process for manufacturing a new device, there is a demand that a pattern having various functional properties, such as hydrophilicity, hydrophobicity, reactivity, and electrical interaction, be formed on an organic substrate by irradiating the substrate with the VUV light. A substrate on which such a pattern is to be formed is made, for example, of a cyclic olefin resin, such as a cyclic olefin polymer (COP) and a cyclic olefin copolymer (COC), and these are used, for example, in biofunctional microdevices, such as a biochip.
Methods of manufacturing a patterned object include, for example, a technique disclosed in PATENT LITERATURE 1 (Japanese Patent Publication No. 5056538 B). In this technique, a substrate on which a SAM is formed serves as a pattern forming substrate, and the SAM on this pattern forming substrate is irradiated with the VUV light via a mask so as to remove a portion of the SAM in a patterned shape. Here, the SAM is irradiated with the VUV light in the presence of a reactive gas containing at least oxygen. In addition, an excimer lamp or the like that emits excimer light having a main peak wavelength of 172 nm is used as a light source for emitting the VUV light.